A list of prior patents which may be of interest is provided below:
______________________________________ U.S. Pat. No. Inventor Issue Date ______________________________________ 1,165,413 Jester DEC 28 1915 3,528,559 Miller SEP 15 1970 3,688,459 Mattix SEP 05 1972 3,789,568 Mattix FEB 05 1974 3,811,241 Mattix MAY 21 1974 3,966,705 Gutierrez DEC 14 1976 4,865,066 Brooks SEP 12 1989 5,228,249 Campbell JUL 20 1993 ______________________________________
The use of plastic laminated wallboards and the like for finishing of counter-tops and back-splashes and shower and bathtub installations in place of ceramic tiles has been common.
Various means of installing the wallboards and fixing them in place have been taught. However, until the joint construction and installation system of the Mattix patent (U.S. Pat. No. 3,688,459), all such prior art systems have various distinct disadvantages such as clumsiness, bulk, unattractiveness, visibility, a lack of security, expense, have leakage problems, are unduly time consuming, or require some degree of skill to obtain exact alignment. Nor have they been easily adaptable to both the counter-top/back-splash and shower/bathtub applications.
Examples of such prior art systems are the U.S. patents to Anglinetti, U.S. Pat. No. 3,420,021; Wilhoyte, U.S. Pat. No. 2,218,273; McBride, U.S. Pat. No. 3,277,617; Hobbs, U.S. Pat. No. 2,677,268; Sperry, U.S. Pat. No. 2,219,714; Gregoire, U.S. Pat. No. 3,376,679; and Schmitt, U.S. Pat. No. 1,672,914.
In the Mattix Pat. No. 3,688,459, although its disclosure provided quite a substantial advance in the art at its time, its approach also needed improvement. In particular, a rabbet or rectangular cut-out is required in the method of attaching the corner lock clip to a wallboard is rather unsophisticated and allows room for error in the exact alignment of the wallboards. In addition, in order to insert a second panel into the clip secured to a first panel, a rectangular cut-out must be made to prevent the clip from adding bulk to the comer. Nor are the lengths of the clip when installed precisely determined due to their angled orientation prior to the insertion of the second panel. This makes measuring the exact width of the panels and cut-out more difficult thereby making a tight and secure comer more difficult to achieve.